"I mean, a dog'll bite if yeh bait it, won' it - but Thestrals have jus' got a bad reputation because o' the death thing - people used ter think they were bad omens, didn' they? Jus' didn' understand, did they?"

A Thestral is a breed of winged horses with a skeletal body, face with reptilian features, and wide, leathery wings that resemble a bat's.

They are very rare, and are considered dangerous by the Ministry of Magic. Thestrals are, undeservedly, known as omens of misfortune and aggression by many wizards because they are visible only to those who have witnessed death at least once (and fully accepted the concept) or due to their somewhat grim, gaunt and ghostly appearance.[1][2][3][4][5][6]

Thestrals can be domesticated and mounted, so they are used as an alternative to brooms, Apparition and other methods of transportation. Once trained, they are very diligent and will quickly carry their owners wherever they wish to go.

Due to their classification as XXXX, only experienced wizards should try to handle Thestrals. Breeding as well as owning these beasts may be discouraged or even illegal without Ministry consent; in fact, wizards that live in areas not protected against Muggles are forced by law to perform Disillusionment Charms on their Thestrals regularly.[6]

Physical appearance

Thestrals have quite a disturbing appearance and the wizards who are capable of seeing them often only describe these creatures as being sinister and spooky. This is because they are seen as having big, bony figures and their dragon-like faces which bear white, glittering eyes that lack both expression and pupils. Additionally, they are lured by the scent of blood.

Being a type of winged horse, most of their anatomy is identical to a horse, excluding their large wings that sprout from their back. Unlike the Abraxan, another breed of winged horses, Thestral's wings do not possess any feathers at all; they have vast, black and leathery wings that are more similar to those of bats.[6]

Their fleshless, lustrous bodies are covered with a translucent and glossy coat. This smooth and dark skin is a bit slippery and so thin that Thestral's bones are clearly defined through the entire extension of their sleek bodies.

These eerie horses have long black manes, as well as a large tail, either with flowing black hair, like horses or ending in a tuft, like zebras.[7]Another distinction is their sharp fangs used to seize and slash their prey.

A Thestral.

Nature

These creatures are seemingly rather dull, though ProfessorRubeus Hagrid states that they are "dead clever", and, in fact, trained Thestrals are smart enough to understand their rider's words when they ask to travel to a specific location.

These magical creatures can be found in dark environments, and the forest is their natural habitat. They communicate with each other through a shrill and strange shriek that resembles some sort of monstrous bird.

They appear to be loyal creatures, able to discern a friend from an enemy. Thestrals would forcefully attack anyone or anything they see as a threat and, in the unusual case of domesticated Thestrals, any enemy of its owners.[8][9]

In the Battle of Hogwarts, Hogwarts' trained flock of Thestrals cooperated with Buckbeak, the Hippogriff, to attack the Giants fighting for Voldemort. It's unclear whether or not wild herds can similarly cooperate with other species.[10]

Diet

Thestrals are carnivorous animals and are attracted to the smell of blood. ProfessorWilhelmina Grubbly-Plank mentions that they often attack birds. This indicates that, naturally, they hunt not only for food in the ground, but also pursue flying prey.

The Thestrals that live within the Hogwarts grounds, in the Forbidden Forest, are properly fed and well trained. They don't attack other creatures or students unless seriously disturbed.

Thestral foal eating a piece of meat

Abilities

The Thestral tail hair is a powerful and tricky substance that can be mastered only by a witch or wizard capable of facing death. It should be noted that this substance can be used as a core in a wand's conception and it was used to create the most powerful wand known by wizards, the Elder Wand. [7]

The most well known ability of these beasts is their invisibility to those who haven’t seen death. In other words, they are only visible to people who have seen someone dying and fully accepted, understood and internalized the concept.

Thestrals have an extraordinary sense of smell and will easily recognize the smell of blood and fresh flesh, even if the source of the scent is rather distanced.

They also have quite a useful sense of direction. The Thestral can understand exactly where their riders need to go. If their riders have a certain destination in mind, they only need to say the destination and the creature will diligently carry them to the intended location - much like owls do with letters.

Their powerful wings are capable of lifting, at least, the burden of two humans plus their own weight.

A Thestral during flight.

Interaction with humans

Even with all their useful abilities, Thestrals are rarely used as methods of transportation due to their reputation as omens of evil and their somewhat dreadful and even distasteful appearance.

When riding a Thestral, the traveller usually holds the creature's mane to ensure balance during the flight (or ride.) To aid the mounting, the wizards also place their legs behind the wing joints to provide safety.

Flying on the back of a Thestral during a long journey is frequently an unpleasant experience, particularly to those who dare riding them without seeing the creature. The high speed flight on an invisible steed can be terrifying. The wind will, eventually, cause a temporary deafness and will force the riders to close their eyes. It is often difficult to keep balance on their slick backs.

The Hogwarts herd is gentle towards humans, they react satisfactorily to caresses and avoid attacking owls. However, taking into consideration the Ministry of Magic classification as "dangerous", this behaviour may be exclusive to well-trained Thestrals,[6] or just mere prejudice from the Ministry.

Rubeus Hagrid, the trainer and breeder of this specific herd, strongly suspects that this is the only trained large group of Thestrals in the whole of Great Britain.

Harry Potter's encounters with Thestrals

Harry Potter first saw the Thestrals at Hogwarts in September of 1995, after having witnessed the murder of Cedric Diggory in June. Harry could not see them that June because he had not yet dealt with what he had witnessed. At first, he wonders why the supposedly horseless carriages are suddenly pulled by such sinister creatures when they are able to move on their own. He points the Thestrals out to Ron Weasley , and realises that Ron cannot see them. Sensing his desperation, Luna Lovegood assures him that she has always been able to see the horses and that he is just as sane as she is. Given Luna's odd habits and beliefs, this statement does not completely reassure Harry.

They were first identified by name by ProfessorWilhelmina Grubbly-Plank, after Hedwig was found injured, when she mentioned that Thestrals sometimes go after birds. They were next mentioned by Hagrid in a Care of Magical Creatures class, where the students were told that they could be used as mounts, and introduced their navigation abilities.

Snape could see Thestrals,[12] presumably as a result of seeing people killed in the First and Second Wizarding Wars, as Dumbledore once asked him "how many men and women" he had "watched die", although Snape had replied that "lately only those whom I could not save".

Media

Behind the scenes

J. K. Rowling also stated that the reason Harry was not able to see Thestrals until the beginning of his fifth year was that when he left Hogwarts in June he had not yet fully come to terms with Cedric's death.[12]

As described in Goblet of Fire, when Harry and Cedric are transported into the graveyard, Harry's scar begins to hurt and then Wormtail kills Cedric. It mentions "A blast of green light blazed through Harry's eyelids, and he felt something heavy fall to the ground beside him." That meant that Harry had his eyes closed when Cedric died and did not know what fell next to him. Therefore, Harry did not actually witness Cedric's death and should not have been able to see Thestrals as a result of it. Despite this, it is canon that Harry can see Thestrals, as it was clearly stated that he could see them in Phoenix, and thus the way in which he witnessed Cedric's death can be described as a consistency error. If one considers it a mistake that Harry was able to see Thestrals, then he should not have been able to see them until either the death of Sirius Black, or Albus Dumbledore, depending on whether witnessing Black falling through the Veil would count.

Harry also had the chance to witness at least two people die before the death of Cedric Diggory in Harry Potter and the Goblet of Fire. His mother was murdered by Lord Voldemort when he was one, and Professor Quirrell in his first year. Despite this, Harry is not able to see the Thestrals until the beginning of his fifth year. J. K. Rowling has explained this stating that he was in his crib when his mother was murdered, and passed out before Quirrell died.[13] It's also possible that when his parents died, Harry was too young to truly understand the concept of accepting someone's death. This creates a paradox in the films, since the first film appears to show Harry seeing Quirrell die.

It may be possible that Bill, Fleur and Kingsley Shacklebolt all saw someone die as they all rode a Thestral during the Battle of the Seven Potters. The explanation is that Kingsley Shacklebolt most likely saw a death during the First Wizarding War. However, who Fleur and Bill saw die is Unknown. It is possible, that, like Hermione, Fleur could not see Thestrals, since she lived in France where the First Wizarding War wasn't as effective, and she was only 4 years old when Voldemort was defeated the first time.

There’s an interesting contradiction in the film. The Thestrals are depicted as having no hair at all, theoretically that would make the existence of an Elder Wand impossible in the film adaptations.

Thestrals also don’t seem to have fangs in the film, at least in the young foals. Instead they have a pointed beak which they use to grab food and then they swallow it, almost without chewing, much like birds eat worms.

In the film adaptation of Harry Potter and the Order of the Phoenix, Ginny, Luna, Ron, Hermione, Neville and Harry all see Sirius die, while in the book, Ginny, Luna, Ron and Hermione are in a different room when Sirius dies, and though Harry and Neville see him die, they can both already see Thestrals.

It should also be noted that in the film, Hermione doesn't see Fred die, and Ron has already seen Peter Pettigrew die. Coincidentally, Peter Pettigrew is never shown dying, just being hit by a spell shot from Dobby.

It is unclear if Nymphadora Tonks can see Thestrals, before she died, as she is unconscious when Sirius died and she doesn't see Alastor Moody die, though she might have died later in the Battle of Hogwarts and might have witnessed Remus Lupin die or others. In the film, she is standing in a tower, and it seems that she and Remus die at the same time, as they're seen reaching out for each other's hands at their last living shot, and then their hands are seen close together when their bodies are shown later, though this might just be a coincidence. So she can most likely would have been able to see the Thestrals if she had lived long enough in the books, but probably not in the films.

Coincedentally, if different parts of the films and the books were considered canon, Hermione wouldn't be able to see Thestrals until she saw Severus Snape die, and she wouldn't have seen anyone else. This happens because she doesn't see Dobby die in the book, and doesn't see Fred Weasley, Bellatrix Lestrange, or Tom Riddle die in the films.